This paper aims at investigating the effect of organic matter
content on the engineering properties of the soil.
The effect of the organic matter on both the consistency limits and strength have been investigated. The results show that the organic
matter increases both the plasticity and the strength of soil.
Mathematical formula is presented in which the unconfined
compression strength of the soil is related to the organic matter
content. It was concluded that increasing the organic matter
content increases the displacement corresponding to the maximum shear stress. In addition, the effect of the organic matter has been studied and the results show that the organic matter increases the compressibility of the soil.
Stabilizing the soil with cement has been investigated as well. The
results show that adding the cement to the soil improves the
strength of the soil and decreases its swelling potential.
Depending on the organic matter content, a mathematical formula
is presented to determine the required cement ratio to treat the
soil to decrease its swelling potential.
